What is the difference between usage of '/' and '\'?

Question

<block class="Magento\Framework\View\Element\Template" name="test"
               template="test/example.phtml" />

In above example for class used '\' and template '/'

use Magento\Framework\Escaper;
const XML_PATH_EMAIL_SENDER = "trans_email/ident_custom2/email";

Again we used both. So when to use '/' and '\'?

Answer 1

const XML_PATH_EMAIL_SENDER = "trans_email/ident_custom2/email";

Magento store data of configuration as '/' format.

Regarding '\' , it's PHP format.